1. Field of the Invention
The present invention relates to interface devices allowing humans to provide control input.
2. Background Art
Portable or handheld consumer electronics, such as cell phones, music players, and remote controls, are continuously increasing their functionality and usefulness. There is a concomitant need to increase the efficiency and intuitiveness of the methods used to interact with and control these devices. One type of user input device that shows promise toward this goal is a rotational input.
Input devices that require a primarily rotational input include knobs, jog wheels, shuttle rings, scroll wheels in computer mice, and the like. These devices typically use rotational input to linearly vary some parameter such as audio volume. The most ubiquitous example is the tuner knob on a radio where the rotational motion of the knob is mechanically translated to linear motion of a frequency indicator. More fully electronic devices may have a knob or other rotational input device that causes linear action on some sort of electronic display, such as changing the length of a bar in proportion to volume as a knob is turned.
A common type of rotational input device for computers is the scroll wheel on a mouse. When rotated by a user, the scroll wheel may control various linear motions and actions in a graphical user interface. These motions may include movement of a scroll bar or the scrolling of text, web pages, or images. Also, individual software applications may incorporate extra functions for the scroll wheel such as the moving the linear indicators for volume and balance in several popular music software applications such as Winamp, musimatch, iTunes, and the like.
For small or portable electronics, knobs have the disadvantage of being rather large and protruding. Also, scroll wheels small enough to fit on portable devices may be too small to be easily usable. Jog wheels are one type of a planar rotational input device more aptly suited to small or portable electronics. Jog wheels are disk-like input devices that are typically freely and continuously rotatable. One example use is in video playback or editing equipment where rotating the jog wheel may cause the display of subsequent or prior video frames with some kind of time indicator displayed to show the relative position of the currently displayed frame.
A second type of rotational input device is a shuttle ring. This may be a ring that surrounds a jog wheel or may be a free-standing disk or knob. Typically a shuttle ring rotates through a fixed angle and when released may spring back to an original position. The ring may sense either the force with which it is rotated away from its original position, the angular distance rotated, or both. A shuttle ring is typically used to select the rate at which a parameter is changed. For example, rotating a shuttle ring may cause video frames to advance at a rate proportional to displacement. Rotating various amounts clockwise may cause various speeds of video fast forward, and counterclockwise rotation may cause rewind. In a similar fashion, rotating various amounts in either direction may cause audio volume or any other parameter to increase or decrease at a certain rate.
Although more planar than knobs, jog wheels and shuttle rings have the disadvantage of being primarily mechanical and, therefore, somewhat large. A relatively new class of rotational input devices that are completely planar is the annular touchpad. This is a planar annulus capable of sensing an angular position of touch and rotational motion. One such sensor is manufactured by Synpatics, Inc. and works by sensing capacitance changes caused by the presence of a finger. Another sensor is disclosed in commonly assigned U.S. Patent Application Ser. No. 60/572,155 titled “Annular Potentiometric Touch Sensor,” filed May 18, 2004, which is incorporated herein by reference in its entirety. Like a knob or a disk, the annular touchpad can indicate rotational motion, the beginning and ending angles of the rotational motion, and the like. But unlike a knob or disk, the annular touchpad can indicate where a user first touches in order to initiate the rotational motion. This is analogous to a knob that could indicate where it was first grasped. The present invention capitalizes on this extra and unique capability of annular touchpads to enhance the efficiency and intuitiveness of user input to electronic devices.
An example system using an annular sensor is the Apple iPod. This device translates rotational input from an annular sensor into a control function. Various control functions include linear motion through menus or song lists, linear adjustment of a volume slider, and the like. The exact control function to which the rotary motion is mapped is context sensitive. The context may change only by means of a select button or other buttons.
What is needed is a human interface that immediately and intuitively allows for selection of functionality and parametric input. This interface should be small, inexpensive and easy to integrate with a wide variety of electronic devices.